Simon: "This is Bert Denly at Brooklands. The silencer makes me think the picture was taken in '26 or so, even though it still shows the early 'straight' rockers."
Roger: "Bert didn't join O'Donovan at Brooklands until April 1923. The Brooklands can rather than the "python" exhaust puts it later than 1924. The cycle parts look very much like the pictures of the Monza record breaking machine in 1924 so I would date the machine as 1924. It is remarkably clean for a Don Norton so that would rule out 1926 making it more likely the pic was taken in 1925."